During the past 20 years in collaboration with a research group at Aerodyne Research Inc., Professor Davidovits and his graduate students have studied gas-liquid interactions for more than 30 gas phase species. The results of these studies provided basic information about the nature of gas-liquid interactions at the interface, including an understanding of how gas molecules enter liquids and how they react at the interface. This work also yielded key parameters required to understand the role of cloud and aerosol chemistry in atmospheric processes such as acid rain formation and stratospheric ozone depletion. The current work in the Davidovits laboratory is focused on the study chemical and optical properties of atmospheric aerosols including soot aerosols. Such aerosols have been shown to have important effects on climate and present serious health hazards. The research utilizes a novel aerosol mass spectrometer developed by Aerodyne Research Inc. in collaboration with the Davidovits group. The research is yielding data that are used to interpret field studies and are expected elucidate the role of aerosol particles in climate forcing.
Representative Key Publications:
“Radiative absorption enhancements due to the mixing state of atmospheric black carbon” Christopher D. Cappa, Timothy B. Onasch, Paola Massoli, Douglas R. Worsnop, Timothy S. Bates, Eben S. Cross, Paul Davidovits, Jani Hakala, Katherine Hayden, B. Tom Jobson, Katheryn R. Kolesar, Daniel A. Lack, Brian M. Lerner, Shao-Meng Li, Daniel Mellon, Ibraheem Nuaaman, Jason Olfert, Tuukka Petäjä, Patricia K. Quinn, Chen Song, R. Subramanian, Eric J. Williams, Rahul A. Zaveri. Science, 337, 1078, 2012.
“The Deposition Ice Nucleation and Immersion Freezing Potential of Amorphous Secondary Organic Aerosol: Pathways for Ice and Mixed–Phase Cloud Formation.” Bingbing Wang, Andrew T. Lambe, Paola Massoli, Timothy B. Onasch, Paul Davidovits, Douglas R. Worsnop, and Daniel A. Knopf. Journal of Geophysical Research-Atmospheres, 117, D16209, doi:10.1029/2012JD018063, 2012
“Modeling organic aerosol from the oxidation of α-pinene in a Potential Aerosol Mass (PAM) chamber, Chen, S., Brune, W. H., Lambe, A., Davidovits, P., and Onasch, T. Atmos. Chem. Phys., 13, 5017-5031, doi:10.5194/acp-13-5017-2013.
“Relationship between oxidation level and optical properties of secondary organic aerosol.” Andrew T. Lambe, Christopher D. Cappa, Paola Massoli, Timothy B. Onasch, Sara D. Forestieri, Alexander T. Martin, Molly J. Cummings, David R. Croasdale, William H. Brune, Douglas R. Worsnop, and Paul Davidovits, Environmental Science and Technology, 2013, 47, 6349-6357,doi.org/10.1021/es401043.
“Chemistry of Alpha-pinene and Naphthalene Oxidation Products Generated in a Potential Aerosol Mass (PAM) Chamber as Measured by Acetate Chemical Ionization Mass Spectrometry”, P. S. Chhabra, A. T. Lambe, M. R. Canagaratna, H. Stark, J. T. Jayne, T. B. Onasch, P. Davidovits, J. R. Kimmel, and D. R. Worsnop, Atmos. Meas. Tech. Discuss., 7, 6385-6429, 2014 www.atmos-meas-tech-discuss.net/7/6385/2014/